Daily oil production in the Gulf of Mexico was almost entirely shut down by mid-morning Tuesday as offshore opreators evacuated platforms and rigs in the path of Hurricane Isaac, federal regulators said.

Workers had evacuated at least 503 production platforms, or about 84 percent of the 596 manned platforms in the Gulf, the Bureau of Safety and Environmental Enforcement, which regulates the oil and gas industry, said in a statement. Forty-nine rigs, or about 64 percent of the 76 rigs currently operating in the Gulf, had also been evacuated.

Offshore operators reported about 93 percent of the wells producing oil were temporarily closed in anticipation of the storm, up from about 24 percent Monday. After the storm has passed, the facilities will be inspected and production at undamaged facilities will resume.